Results 31 to 40 of about 24,009 (260)

1,3-Dipolar cycloadditions of 2-thio-3-chloroacrylamides with diazoalkanes [PDF]

, 2010
2-Thio-3-chloroacrylamides undergo 1,3-dipolar cycloadditions with diazoalkanes leading to a series of novel pyrazolines and pyrazoles. The mechanistic and synthetic features of the cycloadditions to the 2-thio-3-chloroacrylamides at both the sulfide and
Kissane, Marie, Lawrence, Simon E., Maguire, Anita R.   +2 more
core   +1 more source

Deprotonative C(sp3)/C(sp2)–H (Multi)Silylation of (Hetero)Arenes Mediated by NaTMP

Angewandte Chemie, EarlyView.
An operationally simple protocol using a strongly basic sodium amide in combination with sterically emcumbered silicon electrophiles enables the deprotonative C–H (multi)silylation of a myriad of (hetero)arenes. Mechanistic investigations highlight the pivotal role of steric and coordination effects in controlling the regioselectivity and efficiency of
David Sánchez‐Roa, Sophia Belrhomari, Ana McGinley, Clevin Anto Liju, Manting Mu, Max García‐Melchor, Eva Hevia   +6 more
wiley   +2 more sources

Synthesis of tetrasubstituted pyrazoles containing pyridinyl substituents

Beilstein Journal of Organic Chemistry, 2017
A synthesis of tetrasubstituted pyrazoles containing two, three or four pyridinyl substituents is described. Hence, the reaction of 1,3-dipyridinyl-1,3-propanediones with 2-hydrazinopyridine or phenylhydrazine, respectively, affords the corresponding 1,3,
Josef Jansa, Ramona Schmidt, Ashenafi Damtew Mamuye, Laura Castoldi, Alexander Roller, Vittorio Pace, Wolfgang Holzer   +6 more
doaj   +1 more source

Order versus disorder in two isomorphous pyrazolone-substituted diethyl propanedioates prepared using a three-component one-pot reaction under solvent-free conditions

Acta Crystallographica Section E: Crystallographic Communications, 2020
Two new substituted propanedioate esters have been synthesized using a three-component solvent-free thermal reaction between diethyl propanedioate (diethyl malonate), 5-chloro-3-methyl-1-phenyl-1H-pyrazole-4-carbaldehyde and an aryl azide, forming two ...
Tharangini K. Shreekanth, Hemmige S. Yathirajan, Balakrishna Kalluraya, Sabine Foro, Christopher Glidewell   +4 more
doaj   +1 more source

The analgesic effects of anti-inflammatory drugs from the point of view of different pharmacological test methods [PDF]

, 1964
1. The forms of irritation causing inflammation and pain are reviewed, with reference to the significance of histamine, serotonin and bradykinin and in particular to the interrelationship between inflammation and pain. 2.
Wilhelmi, G.
core   +1 more source

Diazo Transfer From Nitrous Oxide Employing Phosphorus Ylides

Angewandte Chemie, EarlyView.
A phosphorus ylide‐mediated strategy achieves the direct fixation of nitrous oxide (N2O) to access diazo compounds, which after intra‐ or intermolecular trapping, afford N2‐containing organic building blocks. This approach provides an alternative to hazardous diazo‐transfer reagents and establishes N2O fixation as a sustainable methodology.
Jhen‐Kuei Yu, Jan Niclas Ludwig, Patrick Wolf Antoni, David Tymann, Max Martin Hansmann   +4 more
wiley   +2 more sources

Symmetric 3,5-Pyrazole and Isoxazole Heterocycles Comprising a Bent Core Unit: Synthesis and Mesomorphic Characterisation [PDF]

, 2015
The synthesis and characterisation of some new liquid crystalline (LC) heteroaromatic compounds containing the five-membered pyrazole/isoxazole rings is reported. Some of the compounds exhibited enantiotropic LC properties.
Hariprasad, S., Srinivasa, H.T.
core   +1 more source

Azide‐to‐Diazo Transformation Facilitated by Michael Addition via Phosphazide Formation

Angewandte Chemie, EarlyView.
A new type of Michael addition based on azide‐to‐diazo conversion is disclosed. This unusual transformation proceeds via 1,4‐addition accompanied by N─N bond cleavage of phosphazide intermediates under practical conditions. The high versatility of the resulting Michael adducts enables the synthesis of a wide variety of organonitrogen compounds ...
Tomoki Mano, Takahiro Yasuda, Gaku Orimoto, Suguru Yoshida   +3 more
wiley   +2 more sources

Key Intermediates: A simple and Highly Selective Synthesis of 5-amino-1-aryl-1H-pyrazole-4-carbonitriles for Applications in the Crop Protection [PDF]

, 2015
A series of six pyrazoles was synthesized by Michael-type addition reaction. The molecules 5- amino-1-aryl-1H-pyrazole-4-carbonitrile (3a-f) were synthesized from (ethoxymethylene)malononitrile (1) and fluorinated and non-fluorinated aryl hydrazines (2a ...
Murguia, Marcelo Cesar, Müller, Diana, Plem, Silvana Cristina   +2 more
core   +2 more sources

Design Rules for Controlling Connectivity, Topology, and Sorting Using Hydrogen‐Bonded Pairs and Aromatic Components in Palladium(II)‐Based Interlocked and Foldameric Systems

Angewandte Chemie, EarlyView.
We have established a set of design rules which combine Pd(II) metal coordination, complementary geometries, complementary interligand hydrogen bonding and π─π interactions for predictable self‐assembly of Pd(II)‐based species such as metallo‐foldamers, cyclic species a metallo‐interlocked clippane. The species persist in a combinatorial mixture due to
Jess L. Algar, Jordan N. Smith, Dan Preston   +2 more
wiley   +2 more sources